If your current method works for the video you might consider wiretap or something for recording the audio at the same time. Other then that I can't really make a recommendation, not a ton of experience recording.

If you lower the resolution and record it at 640x480 in a window on a decently fast machine, Screenflick should do OK. It really depends on how crazy the content of the movie will be. Make sure you turn on "Optimize for: Speed" in Preferences and tick the slider up to around at least Level 2.